Conventionally, when an image forming apparatus, such as a laser printer or a facsimile machine, is sold, an image forming apparatus for demonstration at shops (hereinafter, referred to as “demo machine”) is used so that customers have a better understanding about the product. The demo machine prints out a demo page on which features of the product are described through a simple key operation.
When an error, such as the demo machine running out of sheets, occurs, the demo machine notifies an error occurrence to a customer or a sales person by turning on an LCD, which is disposed on the demo machine, or by displaying error information on a liquid crystal panel.
In JP-A-1-237180, an inspection apparatus for a demo machine is disclosed. The inspection apparatus displays error information on a display unit, when a printer does not respond for predetermined time or more after printing data is outputted. Further, when a signal, such as “sheet empty” or “error stop” is transmitted from a printer side during a printing, a stop time is stored in a stop time storage circuit, and the time is displayed on the display unit.